Tuning mechanism for radio reception, etc.



Aug. 9, 1932. M. ALDEN 7 4 r TUNING MECHANISM FOR RADIO RECEPTION, ETC- Fil ed Dec; 14. 1926 5Sheets-Sheet 1 Aug. 9, 1932. ALDEN 1,871,293

TUNING MECHANISM FOR RADIO RECEPTION, ETC.

Filed Dec. 14, 1926 3 SheetsSheet 2 w IIII/lIIII/IIIIIII IIIIIII/I/IIILI/lI/l Aug. 9, 1932. M. ALDEN TUNING MECHANISM FOR RADIO RECEPTION, ETC

Filed Dec. 14, 1926 3 Sheets-Sheet 3 INVENTOR Patented Aug. 9, 1932 PATENT OFFICE 4 HILTON ALDI'IOF SYBINGFIELD, IASSAGHUSETTS TUNING IEGHANISH FOB RADIO RECEPTION, E'I'G.

Application filedDecember 14, 1926. -serial No. 154,689.-

My invention relates particularly to variable condensers and attachments thereto.

One object is to provide a variable condenser which is simple, reliable and eflicient. Another object is to providea mechanism which can "bereadily assembled in various multiple unit combinations.

Another object is to proyide a simple multiple unit tuner havin separate condensers 30 which can be operate to ether by the fingers of one hand and independently by a movement of one finger relative to'the others. Another object is to providea construction in which a variable condenser and a movable coil can be readily combined. Another objectis to provide a simplified control with a. maximum refinement of tunin 1 lo carrying out the invention in its preferred form I provide a rigid chassis for supporting the various units. Each condenser has a main en'd'plate with sides which support the stator plates. This end plate has a tubular bearing in which the hub of the rotor is mounted. The bearing is adjustable in the endplate and a spring clamp is provided for applying adjustable pressure of the rotor bearing. The various units are mounted in axial alignment and a'controller disc or drum is secured to thehub or shaft of each unit. Preferably these drums are mounted close together for convenience in operation. Where there 'are three or-more units to be mounted-together one shaft will extend throughanother. This latter arrangement may also beused'where there are only two units on the same axis. Details of the invention will be understood from the following description and the accompanying three sheetsof drawings.

Fig. 1 is a plan view of a tuning condenser with three units.

Fig. 2 is a front view of the same. Fig. 3 is a front view of a two unit condenser (on a smaller scale).

Fig. 4 is a front view ofa'two unit condenser with one coil attached to a control drum and thus variable in position with respect to a fixed coil.

Fig. 5 is a vertical longitudinal sectional view of the form shown in Figs. 1 and 2. Fig. 6 is a cross section on the plane of the line 6-6, Fig. 5 showing the rotor fully engaged.

Fig. 7 isa fragmentary detail and section showlng the parts of the endof' the shaft and rotor hub.

F ig. 8 is a perspective view of "the parts for clamping or holding the rotor frictionally in place. 2

Fig. 9 is an exploded perspective showing parts of a single condenser unit. Fig. 10 is an end view of the condenser with the rotor in the disengaged position.

Fig. 11 is a detail view of fragments of one I of the controllers.

The condenser units 14, 15 and 16 have the operating drums or controller discs 17, 18 and 19 respectively.

Each unit as an end plate 20 which supports the stator and rotor members and constitutes a part of the chassis. The chassis has angular sheet metal side plates 21 with posts 22 terminating in flanges 23 which are con.- nected to the plates 20 by fasteners such as rivets 24. The side plates 21 are connected by cross pieces 25 as well as b the plates 20 so as to form a light but rigid ramework.

Each stator consists of side plats 26 with "slotted flanges 27 in which are secured the stator plates 28.- The lugs 29 serve as convenient means for connection to other elements of the circuit. ,The stator is mechanically supported'from the, end plate 20 but insulated from it by the insulating bars. 30. The ends of each bar 30 are secured to the spaced lugs 31 by rivets 32 and its center is secured to the lug 33 by rivet 34'.

Each rotor has a hub 35 and plates 36 which are held in place by alnut 37 and spaced by washers 38. This hub has a conical flange 39 rotatable in a conical seat in the tubular bearing 40. The, bearing is held in place in the opening 41 in the end plate 20 by nuts-42. By

' this means the bearing may be adjusted in a tion to the stator. The rotor and stator by the clamp or brake 43, one end of which is secured to the plate 20 by the screw 44 and the other end 45 has an arcuate flange which extends into the groove 46 in the flange 39. By tightening the screw 47 the clamp may be drawn up so as to resiliently hold the rotor to its seat in the bearing 40.- The spring washer.

48 prevents the screw 47 from working loose.

The lug 49 serves as a stop for the rotor to' limit its rotation. I

The drums or discs 17 and 18 are mounted on the ends of the hubs 35' and 35" of the adjacent condensers 14 and 15 being held in place by the set screws 50 or otherwise for controllin the movement of the rotors. The drum or isc 19 is secured on the shaft 51 which extends through condensers 15 and 16 andhas a flattened end 52 which extends lat-' erally into a slot 53 in the outer end of the outer rotor and is held in place b the cap nut v 54. The other end of the sha t, preferably. extends into the hub 35' so as to assist in holdin the parts in alignment.

ach controller is preferably made up of two parts held together by rivets 55 and with a channel 56 in the periphery for the scale strip 57 which is preferably removable so that it can be replaced when desired. Obviously the strip can be marked in any desired manner as for instance in wave-length or kilocycles or calibrated or logged for certain stations. The edgesof the discs are preferabl knurled as at 58' to facilitate enga ement an movement. A face plate 59 is pre erably provided to facilitate bringing the desired scale marks into alignment.

The construction of the controller drum and indicator is claimed in my application 163,196 filed January 24, 1927.

In the form of tuner shown in Fig. 3 there are only two condensers 14 and 15 with their controllers 17 and 18, the third condenser 16 and its controller 19 being omitted.

In Fig. 4 I have shown a double condenser arrangement with a coil 60 on the end of the shaft 61 which extends through condenser 15.

In the arrangement shown in Fig. 3, it will be obvious that the two controllers 17' and 18 may be operated together with the fingers of one hand or entirely independently of each other. Such a device has the advantage of simplicity of control and in addition it has the important advantage of fineness of tuning with all the gradations and variations possible with the usual independent condensers and without their great difficulty of adjustment. This is particularlyv important now in view of the crowding of the wave bands and the overlapping of many stations.

though there is some friction between the shaft 51 and the rotor hubs 35' and 35", it is negligible compared with the friction developed by the brake or clamp members 43 which frictionally press eachrotor against its seat in its bearing 40. Each condenser is therefore adjustable independently of the others.

It should be understood that other arrangements and changes may be made with- -in the scope of my invention.

Iclaim:

1. A chassis for a multiple unit condenser comprising angularly' flanged sheet metal side plates, each having base flanges and projecting posts arranged in pairs, cross bars connecting the ends of the flanges, cross plates connecting the ends of the posts of each pair, and shaft bearings carried by said cross plates.

2. A multiple unit condenser chassis comprising angular sheet metal side plates with inwardly projecting base-flanges and upwardly projecting pairs of posts with angularly disposed lugs, cross bars connecting the base flanges,cross plates connectin the lugs of each pair of posts, and shaft earings carried by said cross plates.

3. A condenser chassis comprising sheet metal side plates having base flanges projecting toward each other and having upwardly projecting supporting posts arranged in pairs, the outer ends of. said posts being bent inwardly and arranged nearer together than the main portions of the side plates, lugs integral with the ends of said posts and arranged in planes transverse thereto, cross plates secured to the lugs of the respective pairs of posts, and shaft bearings carried by said cross plates.

. MILTON ALDEN. 

